Filtration Efficiency of Inclusions in Lightweight FeMnAl Steels


The efficiency of ceramic foam filters in removing different inclusion populations in a Fe-30Mn-9Al-1Si-0.9C-0.5Mo steel was investigated. A mold design was created utilizing fluid flow and solidification modeling software. The design utilized a common pouring cup attached to two different but balanced gating systems. One runner utilized a ceramic foam filter, while the other runner was unfiltered. Three molds were poured in sequence from a teapot-style ladle. Metallographic samples revealed extensive Al- and Mn-rich oxide bi-films in samples taken before the filter. Samples sectioned after the filter did not contain bi-films. AlN or complex AlN-MnS or AlN-MnO comprised more than 70% of all inclusions. Samples sectioned from the first two molds showed an inclusion removal efficiency of 38% and 39%, respectively. Larger inclusions greater than 3 µm were more efficiently filtered. The third mold with the greatest number of larger inclusions showed the highest inclusion removal efficiency of 55%.


Materials Science and Engineering


Funding was provided by AIST Foundation. This project was supported in part by the Wolf Endowed Funds for metalcasting education and research at Missouri University of Science and Technology.

Keywords and Phrases

bi-films; FeMnAl steel; filtration; nonmetallic inclusions

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Article - Journal

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Publication Date

01 Apr 2020